THE FARMERS' REGISTER. 



Although the facts stated in the latter para- 

 graph of the above quotation may not be entirely 

 correct, yet it is worthy ol inquiry vvheliierthe di- 

 minution in the leriiiity of the lands of lower Vir- 

 ginia may not, in a considerable degree, have been 

 caused by the exhaustion of ihe alkalies, whicli 

 existed in the soil, at the time it was first brought 

 into cultivaiion. 



According to Liebig, " the deveiopement of a 

 plant requires the presence, first, of substances 

 containing carbon, and nitrogen, and capable ol 

 yielding these elements to the growing organism ; 

 secondly, of water and its elements ; and, lastly, 

 of a soil to furnish {he inorganic matters, which 

 are likewise essential to vegetable hie." — p. 56. 

 Water is composed oi iiydrogen and oxygen, and 

 as plants are capable of decomposing and assiuii- 

 laiing its elements, (pp. 122 and 125,) there can 

 never be a deficiency in the supply of these lo 

 growing vegetation, except in time of drought. 

 During the early growth of plants, carbon is lur- 

 nished by the humus ol the soil, in which they 

 grow, but after they have developed their leaves 

 an abundant supply of carbon is obtained Irom the 

 atmosphere, by means of their absorbing power. 

 This supply is so great, that in the opinion of Lie- 

 big, (p. 106,) they no longer acquire any from ihe 

 soil, and return even that which they had extract- 

 ed, during the lormatiun of their first leaves. 

 The remaining organic substance, essential to the 

 growth of plants, is nitrogen. This, according to 

 Liebig, is furnished, to some extent, Irom the at- 

 mosphere, in the form of carbonate of ammonia. 

 This substance is very soluble in water, and con- 

 sequently combines with the moisture of ihe atmo- 

 sphere, and is brought down to the earth with the 

 dews, rain and snow, and thus furnishes, to some 

 extent, this necessary element lor the nourish- 

 ment of plants. The quantity derived in this 

 way, though considerable, is not sufficiently ample 

 to produce a flourishing and vigorous growth ol 

 plants. To preserve the lertilily and produciive- 

 ness of soils, the deficiency of nitrogen must be 

 supplied by the application oi' putrescent manures, 

 which abound in this ingredient. According to 

 Liebig, this may be so easily effecled, that by the 

 application of human excrements, " using, at the 

 same lime, bones and the lixiviated ashes of wood, 

 the excrements of animals might be completely 

 dispensed with." — p. 242. 



From these views it is quite apparent, that but 

 little effort is necessary to prevent our growing 

 crops from suffering from a deficiency in the prin- 

 cipal organic elements, which constitute the appro- 

 priate food of plants. 



But several inorganic matters "are likewise 

 essential to vegetable lile." Liebig informs us 

 that '' moot plants, perhaps all of them, contain 

 organic acids of very difl'erent composition and 

 properties, all of which are in combination with 

 bases, such as potash, soda, lime, or magnesia. 

 These bases evidently regulate the formation of 

 the acids, lor a diminution of the one is followed 

 by a decrease of the other." — (p. 148.) Here are 

 four of the inorganic substances which are most 

 essential to the growth of vegetables. They are, 

 it is true, combined with organic acids, which are 

 necessary to fit them for assimilation, but the quan- 

 tity of the acid is always regulated by the base, so 

 that, if the latter be diminished, the (brmer will be 

 decreased in a corresponding degree; and when- 



ever a base is present the acid will be supplied. 

 We have then but to ILiinish the soil with potash, 

 soda, lime, and magnesia, (if they do not already 

 exist,) when ihe necessary acids, to fit them lor 

 assimilation by the giowing plants, will combine 

 with them. 



'I'he inorganic substances, mentioned above, 

 are all important in consiiluting a good soil, but 

 magnesia is, perhnp?, less so ilian either of ihe 

 others; yei even tins is csseniial lo the vigorous 

 urowih of many vegetables, lor, as we are told by 

 Jjiebig, "all seeds of the gramineoe contain phos- 

 phate of magnesia," (p. 93,) and that without this 

 substance '• llie seeds of corn (wheat) could not be 

 lormed."— p. 201. 



Many soils are, by nature, abundantly supplied 

 with carbonate ol lime. Bat when it does not ex- 

 ist, in soils, it is very important that it should be 

 supplied. Fortunately, the exien-^ive banks of 

 shell marl, in lower Virginia, afibrd Ihe means of 

 doing BO, and no reasonable expense should be 

 spared in accomplishing an oljccl so important in 

 ihe renovation ol exhausted soils. 



Vegetables of all kinds contain, in their compo- 

 sition, more or less of the alkalies. It is very- 

 clear, therelbre, that this ingredient is indispensably 

 necessary to their growth. If a soil nas; been en- 

 tirely exhausted ol ihe alkalies, it must necessarily 

 be completely barren. If it has been only partially 

 exhausted, it will be still capable of producing a 

 vigorous growth of those trees and plants which 

 require only a small supply of the alkalies. But 

 the growth of those which require a large supply 

 must necessarily be much stinted. Thus forest 

 trees, the leaves of which are renewed annually, 

 require Irom six to ten times more alkalies than 

 the pine or fir tree, and hence pines will grow vi- 

 gorously in a soil, where other trees cannot attain 

 maturity, (p. 198.) So 100 parts of wheat straw 

 will yield of ashes 15.5 parts, whilst that of barley 

 yields 8.54, and of oats only 4.42.— p. 199. 



Plants of the leguminosce lamily require very 

 small quantities of the alkalies. Buckwheat, 

 beans, lucerne, clover, and lentils yield less than 

 one per cent, of ashes. — p. 204. 



These lacts are abundantly sufficient to show 

 that the quantity of alkalies, in soils, should be in 

 proportion to the kind of crops intended to be pro- 

 duced. If ihey exist only sparingly, those crops 

 should be avoided which require a large supply, 

 unless the soil should have been furnished by arti- 

 ficial means. Wheat requires not only more of 

 the alkalies than any other crop, but also a consi- 

 derable quantity of the phosphates, and is therefore 

 a very exhausting crop. — p. 205. 



The alkalies being so necessary to constitute 

 a good soil, the question arises how this ingredient 

 is to be supplied to those soils, from which it has 

 been nearly all extracted. This is to be accom- 

 plished first by ceasing lo cultivate those crops, 

 which require a large supply of the alkalies ; and 

 secondly, by furnishing by artificial means, those 

 soils which are deficient, with a due proportion of 

 these essential ingredients. 



Soils are supplied with alkalies, in the natural 

 way, first, by ihe disintegration ofrocks, (p. 195-6) 

 and secondly, by water evaporated from the sea, 

 and falling in the form of rain, snow and dew (p. 

 160 166 7.) But the supply from these sources 

 is too slow and gradual to be relied upon exclu- 

 srvely, and therefore great efforts should be 



